Mobile robot with a flexible deployable tail

ABSTRACT

A mobile robot includes a deployment mechanism and a flexible tail. The flexible tail is attached to the deployment mechanism and extends outwardly from the mobile robot in a deployment direction. Actuation of the deployment mechanism moves the flexible tail and changes the deployment direction of the flexible tail. Movement of the flexible deployable tail allows the used to change the centre of mass of the mobile robot. As well in use the flexible deployable tail can help to stabilize the mobile robot when it is climbing stairs. As well, the flexible deployable tail can help the robot to absorb energy if it contacts a solid object.

FIELD OF THE DISCLOSURE

This disclosure relates to mobile robots and in particular modularmobile robots that have flexible deployable tails that are able tochange the centre of mass of the mobile robot.

BACKGROUND OF THE DISCLOSURE

Mobile robots are well known and used routinely by military, lawenforcement and security forces. As such they are often used inhazardous situations and in stand-off (remote) locations. Accordingly itwould be very useful to provide a mobile robot that can be easilyadapted for different uses. As well, it would be useful to provide amobile robot that is easily serviced. Accordingly a modular mobile robotwould be advantageous. As well, it would be advantageous if at leastsome of the modules were interchangeable between different sized mobilerobots to suit particular or unique missions.

Some modular robots have been suggested. For example a U.S. patentapplication Ser. No. 12/316,311 that was published on Jan. 13, 2011.This application shows a mobile robot with right and left track modules.However, the rest of the robot does not appear to be modular andtherefore if other than the track modules needed repair or replacementthe robot would likely be out of the field until such work could bedone.

Mobile robots are often used for specific tasks and have specific weightand operational requirements for those tasks. For example mobile robotsare used in space exploration wherein the weight of the robot may becritical to the mission. In stand-off operations having an arm that canpick up hazardous objects may be useful for such missions.

Mobile robots often include endless tracks, particularly mobile robotsfor use in unknown terrains or for use in climbing stairs and slopes, ornavigating obstacles. Endless tracks, which are usually formed of a beltwith a number of cleats disposed transversely to the belt's longitudinaldirection, are the ground-contacting portion of some common drivesystems for mobile robots. Due to their high traction compared towheels, endless tracks have found application in many fields, such asmobile robotics, farming, and construction. Further, drive systemsemploying endless tracks can provide a more versatile set ofcapabilities than wheeled systems, for tasks such as navigation overrough terrains and obstacle climbing.

However, current tracks have a number of drawbacks. For instance, theycan experience more friction than wheels and thus require more power todrive, and may cause vibrations when moving and turning. Further, theymay slip off the wheel or sprocket pulley which drives them, possiblydamaging the track or the drive mechanism. If this happens in ahazardous situation where the robot is being operated remotely, it maybe rendered inoperable. The wheel driving them may also occasionallyrotationally slip within the track, causing a loss of locomotive force.

In addition, mobile robots are often deployed in environments whosesurface characteristics are unknown a priori, and may be very uneven,irregular or bumpy. In such situations, the probability of the robotfalling over after losing its balance can be quite high. For situationswhere the robot is being operated remotely in a hazardous situation,falling over can render the robot inoperable. Furthermore, it may berequired that the mobile robot has the capability to climb obstacles,which is generally a risky task as it can quite easily lead to the robottipping over.

Therefore, it would be advantageous to provide a device that overcomesthe aforementioned difficulties.

SUMMARY

A mobile robot has a predetermined size that is one of large, medium,small and back-packable. The mobile robot is for use with a controlunit. The mobile robot includes a chassis, drive system components,power components, a main processor, a communication system, a power anddata distribution system. The chassis has a predetermined size that isone of large, medium, small and back-packable. Drive system componentsare operably attached to the chassis and have a predetermined size thatis compatible with the predetermined size of the chassis. Powercomponents are operably connected to the power and data distributionsystem and operably connected to the drive system components and thepower components have a predetermined size that is compatible with thedrive system components. The main processor is operably connected to thedrive system components, the power and data distribution a system, andthe power components. The communication system is operably connected tothe drive system components, the power components and the mainprocessor. The communication system is for communicating with theoperator control unit. The power and data distribution system isoperably connected to the drive system components, the power components,the main processor and the communication system. The main processor, thecommunication system, and the power and data distribution system are allcompatible with the predetermined size of the chassis and at least oneother size.

The main processor, communication system and the power and datadistribution system may be interchangeably usable in the large, medium,small and back-packable mobile robots.

The drive system components may include drive traction modules operablyconnected to drive transmission modules.

The drive system components may further include a flipper moduleoperably connected to flipper transmission modules. The drivetransmission modules may be one of long track traction modules, shorttrack traction modules, or wheel traction modules.

The mobile robot may further include a core module and the mainprocessor and communication system may be part of the core module.

The mobile robot may include a head module and the power and datadistribution may be part of the head module.

The core module and the head module may be interchangeably usable in thelarge, medium, small and the back-packable mobile robots.

The mobile robot may include one of a large gripper arm module, a smallgripper arm module and a tooling arm. The mobile robot may furtherinclude a PTZ arm module. The mobile robot may further include a cameraand the camera may be interchangeably attachable to the PTZ arm module,the large gripper arm module and the small gripper arm module.

The mobile robot may include a turret attachable to one of the largegripper arm and the small gripper arm. Further, a turret may attachableto the PTZ arm module.

The mobile robot may include weaponry that is interchangeably usable inthe large, medium, small and back-packable mobile robots.

The control unit may be interchangeably usable in the large, medium,small and back-packable mobile robots.

The control unit may be one of an operator controlled unit and anautonomously controlled unit.

The power component may be interchangeable usable with predeterminedsized chassis smaller than the predetermined size chassis of thecompatible power component.

A modular mobile robot for use in association with a control unitincludes a chassis, drive traction modules, drive transmission modules,a self-contained head module, a self-contained power module, and aself-contained core module. The drive traction module is operablyattached to the chassis. The drive transmission module is operablyconnected to the drive traction module. The self-contained head moduleincludes a power and data distribution system and the head module isoperably connected to the drive transmission module. The self-containedpower module is operably connected to the head module. Theself-contained core module is operably connected to the head module. Theself-contained core module includes a main processor and communicationsystem, whereby the core module manages the communication with thecontrol unit.

The modular mobile robot may further includes flipper modules operablyconnected to flipper transmission modules.

The drive traction modules may be one of long track traction modules,short track traction modules, and wheel traction modules. The modularmobile robot may further include one of a large gripper arm module and asmall gripper arm module. The modular robot may further include atooling arm. The modular mobile robot may further include a PTZ armmodule.

A tooling arm includes a housing, a drive system, a lead screw and nutassembly, and a scoop assembly. The lead screw and nut assembly isoperably connected to the drive system such that rotation of the nutdrives the lead screw upwardly and downwardly relative to the housing.The scoop assembly is operably connected to the lead screw. The scoopassembly has an open position and a closed position and movement of thelead screw downwardly responsively moves the scoop assembly from theopen position to the closed position.

The scoop assembly may act as a four bar link mechanism.

The scoop assembly may include a pair of scoops, a pair of links and ashuttle, each scoop pivotally may be attached to the shuttle, each linkmay be pivotally attached at one end thereof to a bracket and the otherend thereof to one of the pair of scoops.

The bracket may be attached to a lower end of the lead screw. Theshuttle may include a stopper which engages a block connected to thehousing.

The drive system may include a motor and gear head assembly. The housingmay include an upper mounting plate and the motor and the gear headassembly may be attached thereto.

The lead screw and the nut assembly may include a guide tube having aslot therein and the lead screw may include a screw pin extendingthrough the lead screw and its motioning is limited by the slot.

The housing may include an upper mounting plate and the motor and thegear head assembly may be attached thereto.

An endless track includes a belt, a plurality of chamfered cleats, aplurality of holes and a dual v-guide. The belt has an inner surface andan outer surface. The plurality of chamfered cleats, each have a contactsurface. The chamfered cleats are attached to the outer surface definingan attachment area, and the contact surface is shaped such that when thetrack is laid on a flat solid surface, each chamfered cleat contacts theflat solid surface with less area than the attachment area. Theplurality of holes in the belt are disposed between the chamfered cleatsand are shaped to allow teeth of a drive sprocket pulley to pass throughand to engage the belt for transmitting force from the sprocket pulleyto the belt. The dual v-guide includes two elongate, parallelprotrusions which are spaced laterally from each other and are attachedto the inner surface.

Each of the plurality of chamfered cleats may have a substantiallyrectangular cross section in a plane perpendicular to the lateraldirection to the track.

Each of the plurality of chamfered cleats may attach to the outersurface at a fillet. Each of the plurality of chamfered cleats may beintegrally formed with the belt.

Each of the plurality of chamfered cleats may have a rubber cover. Theholes may be substantially rectangular.

The two elongate parallel protrusions may extend around the belt. Thetwo elongate parallel protrusions of dual v-guide may be first twoelongate parallel protrusions, and further including at least a secondtwo elongate parallel protrusions. The first and second two elongateparallel protrusions may have rounded edges. The first and at least asecond two elongate parallel protrusions may be spaced longitudinallysuch that the drive sprocket pulley, in operation, is always contactedby at least a portion of the first and second two elongate parallelprotrusions.

The belt may be made of nylon. The dual v-guide may be made ofpolyurethane. The plurality of chamfered cleats may be made of rubber orpolyurethane.

A mobile robot includes a deployment mechanism and a flexible tail. Theflexible tail is attached to the deployment mechanism and extendsoutwardly from the mobile robot in a deployment direction. Actuation ofthe deployment mechanism moves the flexible tail and changes thedeployment direction of the flexible tail.

The deployment mechanism may be a rotational deployment mechanism, andactuation of the rotational deployment mechanism rotates the flexibletail.

The flexible tail may rotate about an axis parallel to the lateraldirection to the robot. Alternatively, the flexible tail may rotateabout an axis parallel to the upward direction from the robot.

Further features of the mobile robot will be described or will becomeapparent in the course of the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The mobile robot will now be described by way of example only, withreference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a modular mobile robot;

FIG. 2 is a partially blown apart view of the modular mobile robot ofFIG. 1;

FIG. 3 is a perspective view of (A) large, (B) medium, (C) small and (D)backpackable mobile robots;

FIG. 4 is a perspective view of the chassis portion of the modularmobile robot of FIGS. 1 and 2;

FIG. 5 is a perspective view of the chassis portion of the modularmobile robot similar to the view shown if FIG. 4 but shown an alternateperspective;

FIG. 6 is a blown apart perspective view of the chassis portion of themodular mobile robot of FIGS. 4 and 5;

FIG. 7 is a perspective view of the chassis portion of the modularmobile robot but showing it configured with a short track;

FIG. 8 is a perspective view of the chassis portion of the modularmobile robot similar to that shown in FIG. 7 but showing it configuredwith wheels;

FIG. 9 is a perspective view of a modular mobile robot similar to thatshown in FIG. 1 but showing a small arm with a turret;

FIG. 10 is an enlarged view of a gripper arm showing a disruptor moduleattached thereto;

FIG. 11 is an enlarged view of the gripper arm of FIG. 10 showing anX-ray module attached thereto;

FIG. 12 is an enlarged view of the gripper arm of FIG. 10 showing anextendable link attached thereto;

FIG. 13 is an enlarged view of the end of the gripper arm of FIG. 10showing a cutter on the gripper;

FIG. 14 is a perspective view of the chassis of a modular mobile robotshowing the head module and core module of FIGS. 4 and 5 in a largerrobot than that shown in FIGS. 4 and 5;

FIG. 15 is a perspective view of a PTZ arm;

FIG. 16 is a perspective view of the PTZ arm of FIG. 15 but showing thecamera module detached therefrom;

FIG. 17 is showing the camera module that can be transferred to anothermobile robot;

FIG. 18 is a perspective view of a modular mobile robot showing theinter-changeability of large and small arms;

FIG. 19 is a partially blow apart perspective view of a modular mobilerobot similar to that shown in FIG. 2 but further including a turret;

FIG. 20 is a perspective view of a mobile robot in the long track modewith a tooling arm attached to the chassis;

FIG. 21 is a perspective view similar to that shown in FIG. 20 but shownthe mobile robot in wheels mode;

FIG. 22 is a perspective view of the tooling arm;

FIG. 23 is a blown apart perspective view of the tooling arm of FIG. 22;

FIG. 24 is a sectional perspective view of the tooling arm of FIG. 22;

FIG. 25 is an enlarged perspective view of the link mechanism of thetooling arm of FIG. 22;

FIG. 26 is an enlarged perspective view of the lead screw and motor ofthe tooling arm of FIG. 22;

FIG. 27 is a perspective view of the tooling arm of FIG. 22 but with aportion of the housing removed and showing the tooling arm at the startor open position;

FIG. 28 is a perspective view similar to that shown in FIG. 27 butshowing the scoops partially closed;

FIG. 29 is a perspective view similar to that shown in FIG. 27 butshowing the scoops closed;

FIG. 30 is a perspective view of an embodiment of the belt with rubbercover;

FIG. 31 is an enlarged perspective view of a portion of the belt withrubber cover with cleats shown in FIG. 30;

FIG. 32 is a side view of the belt with rubber cover of FIG. 30;

FIG. 33 is a sectional view of the belt with rubber cover of FIG. 30taken through one of the cleats;

FIG. 34 is an enlarged side view of one of the cleats of the belt withrubber cover of FIG. 30;

FIG. 35 is a side of another embodiment of the track;

FIG. 36 is a sectional view of the track of FIG. 35 taken through one ofthe cleats;

FIG. 37 is a top view of the track of FIG. 35;

FIG. 38 is an enlarged top view of a portion of the track of FIG. 35;

FIG. 39 is a blown apart perspective view of a portion of the track ofFIG. 35 with a sprocket pulley;

FIG. 40 is a perspective view of a the track and sprocket pulley of FIG.39;

FIG. 41 is perspective view of an alternate embodiment of the trackshowing a plurality of elongate parallel protrusions;

FIG. 42 is a perspective view of an alternate embodiment of the mobilerobot including a flexible tail;

FIG. 43(A) to (F) are a series of side views of the mobile robot of FIG.42 shown on stairs, with (A) showing the mobile robot approaching thestairs, (B) showing the flexible tail in front of the robot on thestairs, (C) showing the tail in front of the robot as the robot startsto ascend the stairs, (D) showing the tail behind the robot as the robotstarts to ascend the stairs, (E) showing the robot further up the stairsand (F) showing the robot at the top of the stairs; and

FIG. 44 is a side view of the mobile robot of FIG. 41 showing the use ofthe flexible tail on stairs.

DETAILED DESCRIPTION

The systems described herein are directed, in general, to modular mobilerobots, to interchangeable features for use therein, to a tooling armfor use therewith, to an endless track for use therewith and to aflexible tail. Although embodiments of the mobile robot are disclosedherein, the disclosed embodiments are merely exemplary. Furthermore, theFigures are not drawn to scale and some features may be exaggerated orminimized to show details of particular features while related elementsmay have been eliminated to prevent obscuring novel aspects. Therefore,specific structural and functional details disclosed herein are not tobe interpreted as limiting but merely as a basis for the claims and as arepresentative basis for enabling someone skilled in the art to a mobilerobot.

Referring to FIGS. 1 and 2 an embodiment of the modular mobile robot isshown generally 10. Mobile robot 10 has a number of features that aremodular. As well, some of the modules or components are interchangeablebetween mobile robots of different sizes.

Mobile robots that have interchangeable components are particularlyuseful for a user that has a big fleet of mobile robots. By havingmodules that are usable in different sized mobile robots it keeps inreserve a series of different components that are usable in differentrobots, thus making it easier to keep the fleet running. In many fleetsthere are multiple sizes of mobile robots. By way of example as shown inFIG. 3 there may be a large robot FIG. 3(A), a medium sized robot FIG.3(B), a small robot FIG. 3(C) and a robot that fits into a backpack FIG.3(D). By way of example only the large robot may be L×W×H 139×66×78 cmwith a weight of 250 kg, the medium robot 98×50×82 cm with a weightwithout payload of 125 kg, the small robot 71×54×50 cm with a weight of60 kg and the back-packable robot 60×35×23 cm with a weight of 15 kg.Typically the large and medium robots are used for neutralization andhandling of large payloads; the small robot can be used forreconnaissance and handling of small payloads; the back-packable can beused for surveillance and reconnaissance.

Components that may be interchangeable between robots of two or moresizes are the control unit, communication components, electronicscomponents, power components, external sensors, internal sensors,cameras and weaponry. The communication components and a main processormay form part of a self-contained core module which may beinterchangeable between different sized robots. Power and datadistribution system may form part of a self-contained head module whichmay be interchangeable between different sized robots. A self-containedpower module may be downwardly compatible with different robots meaningthat if it is sized for a particular size of chassis it will work withthat sized chassis and smaller chassis. In contrast external componentssuch as a large gripper arm, small gripper arm and PTZ arm are upwardlycompatible meaning that if the arm is sized for a particular size ofchassis it will work with that sized chasses and larger chassis. Aswell, software programs that control specific tasks may beinterchangeable between different sized robots. For example tasks suchas auto navigation and auto grasping of tools from a tool rack would beinterchangeable. As well, software that controls the driving functionand software that controls the PTZ could be interchangeable. Softwarethat controls the sensors, software for relay control, software forpower distributions, software that controls weaponry where the weaponryis interchangeable and software for video selection could each beinterchangeable. However, software that controls the flipper, softwarethat controls the gripper arm and software that controls the PTZ armwould be specific to the particular size of those components.

It will be appreciated by those skilled in the art that not all of thecomponents or modules may be interchangeable between different sizedrobots. Specifically the modules associated with the chassis are notinterchangeable between different sized robots. More specifically theself-contained head, core, and power modules (described in more detailbelow) would be interchangeable. Accordingly, the components associatedwith the chassis, the traction, the transmissions and the power wouldnot be interchangeable. Components such as the gripper arm, PTZ (pan,tilt and zoom) arm and tools could be upwardly compatible in that thecomponents designed for a smaller robot could be used on a larger robot;however it is unlikely that the smaller components would provide thefunctionality of the larger robot. The core module, the head module andthe power module are described as being self-contained since each iscontained in a housing such that it can be easily removed and replaced.The core module, the head module and the power module are completemodules, which are self-contained modules that can be easily removed andreplaced in a particular robot or used in other mobile robots. Morespecifically in one embodiment the core module has processor,communication interface card, wireless transceiver for two-way data andaudio, one-way video, DC-DC converter inside. The core module is the“brain” of the robot. It accepts task commands from the control unit andanalyses and translates the task commands then issue to differentmodules and receives feedbacks from these modules via its multipleserial ports. It also provides Ethernet, USB, RS232, RS485, RS422 andVGA interface to users so the users can develop their own software tocontrol the robot. The power module integrates high capacity Li-Polymerbattery, DC-DC converter, and control relays. The output interfaceconnector on the power module includes the power switch pins, the powerrelay coil pins, and the 12 VDC, 24 VDC, and 37 VDC output pins. Thepower outputs are isolated from the other modules by the power switchand power relay contacts, which means only after the power switch andpower relay are on (manually or remotely), the 12 VDC, 24 VDC and 37 VDCwill be output to the external. The head module in the robot acceptspower input from the power module and control signal input/output fromthe core module and distributes power to all the different modules,including by way of example the drive transmission module, flippermodule, gripper arm module, PTZ arm module, and upgrade module. Thepower and signal distribution is realized by hard wire inside the headmodule to minimize any extra processing delay. The head module alsomanages the cameras, lights(visible and InfraRed), picture-in-picturedisplay, the platform disruptor and laser control, and the relaycontrol.

As well, it is useful to have a mobile robot wherein the functionalityof the robot can be changed by changing a component or a module. Forexample arms of different sizes may be attachable to the same robot ordifferent end effectors may be attached to the same or different arms.

One embodiment of the mobile robot described herein is constructed of aseries of modules. This makes it easy to change from a track robot to awheel robot or from a long track robot to a short track robot. As well,when a robot is in need of repair, the robot is designed such that amodule can be removed and a replacement module may be easily installed.

Mobile robot 10 as shown in FIGS. 1 and 2 is a modular mobile robot.Robot 10 includes a chassis 12, drive system components, powercomponents, electronic components, arm components and other componentsto preform specific tasks.

The drive system components are attachable to the chassis 12. The drivesystem components include drive traction modules and drive transmissionmodules. Referring to FIG. 6, the drive module shown herein is a longtrack traction module 14 and it also includes a flipper module 16 andthe transmission module is a drive transmission module 18 and a flippertransmission module 19. Note that mobile robot 10 will typically includethe flipper transmission module 19 whether the flipper module 16 is inuse or not. Thus the users can easily reconfigure the robot among ashort track, long track with flipper and wheel configuration. However ifthe user knows that it will not be using the flipper module 16 theflipper transmission module 19 need not be used.

The power module 20 includes battery and multiple voltage DC-DCconverters, and provides all the voltages and the power for the entirerobot. The core module 22 includes the main processor and communicationsystem, and manages the communication to the control unit for all themodules. It is operably connected to the other modules. The core modulereceives commands from the control unit and then commands the othermodules. The core module controls the motion of the robot through thedrive transmission module 18 and the flipper transmission module 19. Thecontrol unit (not shown) is typically situated remote from the robot.The control unit may be an operator control unit or an autonomouslycontrolled unit. The control unit might also include a hybridcommunication system that includes a relay unit.

The head module 24 is a power, data and communication distributionmodule, and an interface module to external sensors. The head module isoperably connected to the power module 20 and to the core module 22. Aswell, it is operably connected to the other modules. The head module 24distributes the power from the power module 20 and it distributes thecommands from the core module 22. The head module 24 controls allaspects of the mobile robot. For example, it passes the power andoperating instructions to the drive transmission module 18 and theflipper transmission module 19, as well, through another channel ittransmits power and operating instructions to other components such asthe gripper arm, the PTZ arm, fiber optical components. The head module24 also distributes power such as 12V and operating instructions tointernal and external sensors components and any weaponry. In theembodiment shown herein the head module 24 is configured to interfacewith up to two sensors with a serial communication interface. Inaddition, the head module 24 controls the laser pointer, disruptor andrelay outputs 69 and 70 on the platform.

Mounted with the head module 24 are a camera 71 and two visible 72 andIR 73 lights. The head module 24 is provided with a plurality of ports.For example there is provided a PTZ arm port 74, a gripper arm port 75,a battery charger port 30, a Wi-Fi port 32. PTZ arm port 74 and gripperarm port 75 provide the power supply, the communication and the videosignals to the respective arm. The arm function is defined in itsindependent control box. The head module 24 also may include specificinternal sensors such as a temperature sensor, a compass, aninclinometer and a battery power sensor. As well, the head module mayalso have sensors which may include gas sensor and environmental sensorssuch as chemical, biological, nuclear and explosive (CBRNE) sensors.Alternatively the CBRNE sensors may be in a separate module that isattachable to the chassis or to one of the gripper arms as a payload.These sensors may be either internal or external.

In addition, the head module includes software to control the sensors,software for relay control, software for power distribution, softwarefor data distribution and software for video selection.

The chassis 12 is generally a box 34 with a hinged lid 36. A pair ofrails 38 is attached to the outside of the chassis. The rails 38facilitate the attachment of the components such as the gripper arm.

In the embodiment shown herein some of the modules are mechatronicsmodules in that they have the electronics and mechanical partsintegrated. For example, the flipper transmission module 19 has motor,gear head, encoder, angular position sensor, brake, servo motor driver,transmission gear pairs, cam, mechanical structure, etc. The largegripper arm module 28 has motors, gear heads, encoders, angular positionsensors, payload interface, weapon control interface, and the mechanicalstructure, links, and gripper fingers integrated. The PTZ arm 26 has amotor, motor driver and power conditioning.

In the embodiment herein, the core module 22 has a plurality of serialports, and can be configured to multiple serial communication protocolstandards. Among them, serial ports in the core module are connected tothe head module 24, and from there connected to different modules. Inthe embodiment herein the serial ports from the head module areconnected to: the drive transmission and flipper transmission modules 18and 19, the gripper arm 28, the PTZ arm 26, the fiber optical module 44.In addition other modules or components may also be connected to theserial ports. All the communications are initiated by the core module22. Only the core module 22 can “talk” to different modules and themodules will not “talk” to each other directly. However, the head modulepasses the information or “talk” to the other components. The coremodule routes the communication through the head module 24. It will beappreciated by those skilled in the art that the number of ports in thecore module 22 and the head module 24 may vary depending on the specificuse and specifications for the mobile robot.

The upgrade module 46 includes fiber optic spool and cable andadditional sensors. The upgrade module is only for use in the large andmedium mobile robots. The fiber optic cable is connected to the controlunit and is to communicate with the core module 22.

It will be appreciated by those skilled in the art that embodiment ofthe modular mobile robot shown and described herein provides the userwith a number of options in regard to the configuration of the robot andthe components attached thereto. For example the robot has three basictraction configurations; namely the long tack traction module 14 andflipper modules 16 attached to the chassis, as shown in FIGS. 1, 2 and 4to 6; a short track traction module 52 attached to the chassis as shownin FIG. 7; and wheel traction module 55 attached to the chassis as shownin FIG. 8.

As well the embodiment of the modular mobile robot shown herein allowsfor the reconfiguring of the arm and payloads for specific missions. Forexample, referring to FIG. 9, an alternate gripper arm 54 which issmaller than gripper arm 28 may be attached to the rails 38 and operablyconnected to the same ports as gripper arm 28. Gripper arm 28 or gripperarm 54 may have a variety of different components attached thereto. Forexample a disruptor 56 or a laser pointer 57 or a weapon 59 all as shownin FIG. 10 or an X-ray 58 as shown in FIG. 11 may be attached to thegripper arm. Alternatively the gripper arm may include an extendablelink 60 as shown in FIG. 12. The gripper may include a cutter 62 asshown in FIG. 13.

A number of modules may be interchangeable between different sizedmobile robots. FIG. 14 shows a chassis 64 of a modular mobile robot 65which is similar to chassis 12 but larger. Chassis 64 has the headmodule 24 and the core module 22 positioned therein.

Referring to FIGS. 15 and 16, as discussed above a number of modules maybe interchangeable between different mobile robots and between mobilerobots of different sizes. By way of example the PTZ arm 42 has a camera66 attached thereto. Camera 66 is attached with a plurality of screws 68and thus it can be detached by removing the screws. It can then be movedfrom the PTZ arm 42 to a gripper arm 28 as shown in FIG. 17. FIG. 18shows an embodiment with (3) three arms that could be attached to theplatform 12. The arms are the PTZ arm 26, the large gripper arm 28 andthe smaller gripper arm 54. FIG. 19 shows an embodiment that includes aturret 76 wherein the large gripper arm 28 is attachable to the turret76 and the PTZ arm 26 is attachable to a platform 77 that extends to oneside of the large gripper arm 28. The small gripper arm 54 shown hereinhas a turret incorporated therewith, however, the turret could be aseparate module to which a small gripper arm is attached. Any one of thearms 26, 28 and 54 could be attached to turret 76 thereby allowing thearm to rotate 360 degrees.

The embodiments of the modular mobile robot may also include modulesthat may control specific functions. For example an auto navigationmodule which is operably connected to the core module can control themotion of the robot. An auto navigation module includes a processor anda plurality of sensors, such as IMU (inertia measurement unit),inclinometer, gyro, and LIDAR (light detection and ranging). This modulewill calculate the path based on the sensor feedback and send the motioncommands to the core module. There may also be a module forautomatically controlling specific functions of the gripper arm such asan automatic stow motion or an automatic deploy function, as well asautomatically grasping and changing tools from the tool box. This autograsping module includes a processor and a plurality of sensors such asforce and tactile sensors.

Referring to FIGS. 20 and 21, a tooling arm 80 is shown attached to amobile robot 10. It will be appreciated that this tooling arm 80 may beattached to mobile robot 10 when it is in a number of differentconfigurations. By way of example, as shown in FIG. 20 it can beattached to a mobile robot in the long track mode or as shown in FIG. 21in the wheel mode. The tooling arm 80 is particularly useful wherein therobot is a micro-robot and weight is important. The tooling arm 80 isparticularly useful for scooping and collecting small samples. Thetooling arm 80 enables sampling and digging to a predetermined depth andfor capturing and stowing a sand or soil sample. Thus the tooling arm isparticularly useful for robots that are used in lunar or Martianexplorations.

Referring to FIGS. 22 to 24, the tooling arm 80 includes a drive system82, a lead screw and nut assembly 84, a scooping assembly 86 and ahousing 88. The tooling arm 80 may be fixedly mounted in the front ofthe mobile robot 10 as shown in FIGS. 19 and 20. Alternatively thetooling arm 80 may be releasably attachable to rails 38 (shown in FIGS.1 to 19).

Drive system 82 may be a motor and gear head assembly. The drive system82 is fixedly mounted on an upper mounting plate 94 which is fixedlyattached to the housing 88. Lead screw and nut assembly 84 includes alead screw 100, a nut 102 (as best seen on FIG. 24), a guide tube 96with a vertical slot 98 therein (as best seen in FIG. 26), and a lowermounting plate 104 which is fixedly attached to the housing 88. Nut 102is rotatably attached to lead screw 100. A screw pin 105 extends throughthe lead screw 100. Screw pin 105 extends through lead screw 106 and itsmotion is limited within the slot 98 of guide tube 96. Guide tube 96 isfixedly mounted on upper mounting plate 94. Drive system 82 is operablyconnected to nut 102 by a pair of meshing spur gears 107 (best seen inFIG. 23). Meshing spur gears 107 are fixedly connected to nut 102 andthe drive system 82, respectively. Thereby, the lead screw 100 movesupwardly and downwardly in a generally vertical fashion relative tohousing 88 and the chassis of the mobile robot.

The scoop assembly 86 includes a pair of scoops 106, a pair of links 110and a shuttle 108. Each scoop 106 is pivotally attached to a shuttle108. Each link 110 is pivotally attached at one end thereof to a scoop106 and at the other end thereof to a bracket 112. Bracket 112 isattached to the bottom end of the lead screw 100. Thus as the lead screwmoves up and down the bracket 112 moved up and down. Shuttle 108 has apair of generally vertical slots 114 formed therein. A post 116 extendsoutwardly from the link 110 where the link is pivotally attached to thebracket 112. Post 116 slidingly engages the slot 114 in shuttle 108.Thescooping assembly 86 acts as a four bar link mechanism wherein theslider is the lead screw 100; the coupler link is link 110; the slidelink is the scoop 106; and the frame is the shuttle 108.

Housing 88 is provided with a block 118 which is adapted to engagestopper 120 extending outwardly from shuttle 108 as best seen in FIGS.23 and 29.

FIGS. 27 to 29 show the tooling arm 80 in use. The scoop assembly 86 hasan open position as shown in FIG. 27 and a closed position as shown inFIG. 29. The scoop assembly 86 moves from the open position to theclosed position responsive to the movement of the lead screw 100 wherebyas the lead screw 100 moves downwardly the scoop assembly 86 moves fromthe open position to the closed position. The scooping assembly 86 iscontrolled for opening and closing using the downward force of the leadscrew 100 acting on links 110. The lead screw 100 moves generallyvertically relative to the chassis and does not rotate. Tooling arm 80has two degrees of freedom (DOF). More specifically tooling arm 80 usesone drive system 82 to realize two motions such that lead screw 100provides linear motion which is translated into rotational motion byscoops 106 rotation such that they close and open. Lead screw 100 movesupwardly or downwardly depending on the direction of rotation of themotor 90. When lead screw 100 moves downwardly the scoop assembly 83moves downwardly with the shuttles 108, links 110 and scoops 106 movingdownwardly together as a unit. The motion of the shuttle 108 will stopwhen the shuttle's stopper 120 is obstructed by or engages a block 118mounted on the housing 88. When the shuttle stopper 120 engages theblock 118 the shuttle stops moving downwardly with the downward motionof the lead screw 100. Motor 90 continues to drive lead screw 100downwardly which in turn causes links 100 to move downwardly in slots114 of shuttle 108. This in turn causes scoops 106 to dig in and closeand scoop up anything in their path. Once the scoop is fully closed, thedrive system 82 reverses to drive lead screw 100 upwardly, which in turnlifts the shuttle 108 and scoops 106 upwardly and thus closes scoops106. The motor 90 is stopped when the scoops 106 are clear of thesurrounding sample. To open the scoops and deposit the sample the motor90 reverses to drive the lead screw 100 upwardly which causes theshuttle 108 to move upwardly until contacting the lower mounting plate104. The motor 90 continues to drive the lead screw 100 upwardly whichin turn cause the links 100 to move upwardly in slots 114 of shuttle108. This in turn causes the scoops 106 to open and release the sampleinside.

A sampling sensor 148 may be mounted inside scoop 106 to measure ifsample is collected. A distance sensor may be fixedly mounted on theshuttle 108 to detect the distance between scoop 106 and the ground.

Referring to FIGS. 1, 30 to 34, an endless track is provided, comprisinga belt 131 having an inner and outer surface 132, 134, and a pluralityof cleats 136 attached to the outer surface 134. The attached cleats 136generally project outwardly from the belt 131 and provide much of thetraction and gripping capabilities of the endless track.

In some embodiments, the cleats 136 are attached to the outer surface134 defining an attachment area, and a contact surface 138 which has asmaller surface area than the attachment area. In other words, thecleats 136 may be chamfered such that when the track is laid on a flatsolid surface, each chamfered cleat 136 contacts the flat solid surfacewith less area than the attachment area. This reduces the friction andvibration of the track during turning and driving. In order to maintainthe traction provided by using an endless track, while still reducingfriction and vibration by using chamfered cleats 136, the cleats 136 maybe chamfered or rounded only on edges which are substantially parallelto the longitudinal direction of motion of the track 130. For example,for cleats 136 are substantially rectangular prism-shaped beforechamfering during manufacturing, each of the plurality of chamferedcleats 136 remains substantially rectangular when viewed in a lateraldirection to the track. For example, as shown in FIG. 36, cleats 136viewed along section A-A appear to have a trapezoidal top, where the topcorners in this view (which are edges in 3 dimensions, parallel to thelongitudinal direction of track motion) have been chamfered to reducethe surface area of the contact surface 138. However, when viewed in alateral direction, such as shown in FIG. 35, the cleats 136 appearsubstantially rectangular. The cleats 136 may further have fillets 140or other reinforcement at the connection between them and the outersurface 134 of the endless track, as shown in FIGS. 31, 34 and 38. Thecleats 136 may be made of any material known to be suitable for theapplication by those skilled in the art; for example, rubber orpolyurethane. In embodiments where the cleats 136 are made of rubber,the cleats may have a rubber coating. The rubber may be soft forreducing vibration and flexible for bending. The properties of the coverrubber may be as follows: hardness—80 shore A, tensile strength—13800psi, elongation—1380%. Further, it will be appreciated that the cleats136 may be integrally formed with the belt.

In some embodiments of the endless track, a dual v-guide 142 is attachedto or possibly integrally formed with the inner surface 132 of the belt131. With reference to FIGS. 35 to 40, the dual v-guide 142 comprisestwo elongate, parallel protrusions which are spaced laterally from eachother. This lateral spacing provides a groove within which a wheel,sprocket pulley 146 or other track driving mechanism may reside andprovide driving power to the endless track. The dual v-guide 142 servesto keep such a driving mechanism in line with the track 130 and preventsslipping out of the track 130 laterally. It is noted that the dualv-guide 142 may be continuous and extend around the track 130, or thetrack 130 may comprise a plurality of elongate parallel protrusions(equivalent to a dual v-guide 142 broken into a plurality of protrusionsections as shown in FIG. 41). In embodiments with a plurality ofprotrusion sections, the shape of the protrusion sections may bedesigned such that the driving mechanism doesn't snag on them when theprotrusion sections engage the sides of the driving mechanism, forinstance, by rounding or chamfering edges on the protrusion sections.Further, in such embodiments, the protrusion sections may belongitudinally spaced such that the driving mechanism, during operation,always has at least a portion of a protrusion section on either side ofit. Furthermore, it will be appreciated that the dual v-guide 142 maycomprise a different material from or the same material as the belt 131,and it may be integrally formed with or attached to the belt 131. Thematerial of the dual v-guide 142 with C-section is a thermoplasticpolyurethane molding compound. Its physical and mechanical propertiesare: specific gravity—1.136, tensile strength at break—6200 psi, tensileelongation at break—600%, tear strength—434PLI, shore hardness—70.

In some embodiments, the track 130 may have holes 144 in between thecleats 136, as shown in FIGS. 35 to 40. The holes 144 are shaped toallow the teeth 148 of a driving sprocket pulley 146 to pass throughthem and to engage them for transmitting force to the track, as shown inFIG. 40. Such embodiments of the endless track prevent rotationalslippage of the driving mechanism within the track, thus allowing muchmore force to be transmitted through them than in the case of a simplepulley drive mechanism. Further, embodiments of the endless track withholes 144 may be lighter than endless tracks with added inner lugs forengaging sprocket teeth 148. It will be appreciated that embodimentswith holes 144 need not comprise a track 130 with material removed fromit; for example, the track may comprise two belt halves which areattached to one another by the cleats 136 to form the track. Further, itwill be appreciated that the track 130 may be reinforced in keylocations, such as, for example, around the holes 144 or cleats 136. Thetrack 130 may be made of any material known in the art to be suitablefor use in an endless track; in non-limiting examples, it may compriserubber, or urethane, or steel.

In this embodiment belt 131 is a TTA-1500 belt manufactured from NITTACorporation. Belt 131 has a 2.4 mm thickness. Its major structure iscomposed of Nylon core and Nylon fabrics. Its properties includes:tensile strength—450 N/mm, elongation at break—25%, standardtension—1.0%, working load at 1%-22.5 N/mm, temperature range—−20 to+80° C., coefficient of friction (steel)—0.2 to 0.3.

In embodiments of the endless track with a continuous dual v-guide 142,each protrusion may be shaped such that it increases the second momentof area of the track to provide enhanced stiffness with very littleadditional mass. In such embodiments, it will be appreciated that talland slender protrusions provide the highest gain in stiffness peradditional mass. In embodiments the belt 131 comprises holes 144 toengaged sprocket teeth 148, the dual v-guide 142 may reinforce the trackto compensate for the reduced stiffness due to the holes 144. Further,chamfered cleats 136 may be additionally included and positioned toreinforce the areas of the track having holes 144. In such embodiments,in addition to their primary functions, the dual v-guide 142 provideslongitudinal bending stiffness to the track and the cleats 136 providelateral bending stiffness to the track.

Track 130 is composed of belt 131, rubber cover with cleats 136, andV-guide 142. FIGS. 31 to 34 show the belt 131 and the rubber coveradhered together, this is the first step of the track 130 construction.The second step is punching holes 144 on the combination of the belt 131and the rubber cover. The last step is to attach V-guide 144 on the belt131 to make the track 130 as shown in FIGS. 35 to 40.

As shown in FIGS. 42 to 44, a mobile robot is provided comprising aflexible tail 150 which is deployable in various directions extendingoutwardly from the mobile robot. In some embodiments, the flexible tail150 is deployable in front of and behind the robot. The flexible tail150 is attached to a deployment mechanism. In such embodiments, the tail150 may be mounted to the robot in an actuatable rotatable manner suchthat upon actuation, the tail 150 changes its deployment direction fromin front of the robot to behind the robot, or vice versa. The tail 150may be rotatable about an axis parallel to a lateral direction to arobot, in which case the tail 150 flips over the robot whentransitioning; or the tail 150 may be rotatable about an axis parallelto an upward direction from the robot, in which case the tail 150 may bedeployable in front, behind, to the sides of the robot, and positions inbetween. The flexible tail 150 may be mounted to the robot in any wayknown in the art, such as but not limited to, on a disk, wheel,sprocket, gear, or shaft, and may be removable.

The flexible tail 150 may be made of any material, be of any length, andbe of any cross sectional shape such that it can support itself as acantilever beam. Usually, the determination of the flexible tail length(L) depends on: (1) the structure parameters of the platform such as thecenter distance (C) between the front and rear pulleys/wheels and thepulley/wheel diameter (D); (2) the obstacle height (H) to be surmounted,or stairs span (L′) to be climbed. For example, if the design isrequired to climb the stairs with L′ span, the flexible tail length Lcan be obtained based on the following equation,

$\begin{matrix}{L \geq \sqrt{\left( {{2L^{\prime}} - \frac{c}{2}} \right)^{2} + \frac{D^{2}}{4}}} & (1)\end{matrix}$

In non-limiting examples, the tail 150 may be made of any material whichhas sufficient strength, stiffness, and flexibility. It could be metalmaterial such as alloy, spring steel, etc; or non-metal material such asfiber glass or rubber, and it may have a rectangular, circle, orelliptic cross section. For example, in the embodiment shown in FIGS. 42to 44, the flexible tail 150 has a rectangular cross section and is madeof spring steel. The tail 150 is attached at the centre (longitudinally)of the robot. In this embodiment, width of the tail 150 has been chosento be much larger than its thickness; this prevents the tail 150 frombending laterally and keeps it in its preferred deployment directionrelative to the robot when experiencing side loads, such as while therobot turns. It will be understood that the relative dimensions notedherein are included for didactic purposes and are non-limiting.

The flexible tail 150 provides a number of advantages for mobile robots.For example, when it is deployed or its deployment direction is changedby rotating it, it can be done in a rapid manner because of its abilityto absorb energy by deforming. Thus, the flexible tail 150 will have amuch lower chance of breaking itself or the robot it is attached to whenit impacts a solid surface. In a similar scenario, if the flexible tail150 is deployed ahead of a robot while the robot is driving forward, ifthe tail 150 contacts a solid object (e.g. a wall or a large rock), itwill not transfer the impact energy directly to the robot, and willinstead deform to absorb it. If the robot is dropped or it falls, theflexible tail 150 may absorb some of the impact energy thus cushioningthe robot's fall. Further, the flexible tail 150 allows the centre ofmass of a robot to change, and is compliant to uneven terrain whenresting upon it, thus granting the robot a more stable stance on suchuneven terrain.

It is noted that, when deployed in certain configurations (such as thatshown in FIGS. 42 to 44), the flexible tail 150 may increase thefriction experienced by the robot during turning. In embodiments with arobot comprising a flexible tail 150 and endless track as described inthe foregoing, this friction can be reduced by using chamfered cleats136 on the endless track. In such embodiments, the advantages of aflexible tail 150 can be achieved without the loss in locomotiveefficiency when maneuvering the robot.

While the mobile robot shown in the figures is a robot, it will beunderstood by one skilled in the art that the mobile robot comprisingthe endless track and/or the flexible tail described herein may be anynumber of robots. In non-limiting examples, the mobile robot may be arobot; a construction robot such as a backhoe, bulldozer, or crane; afarm robot such as a harvester or tractor; a military robot such as atank; or a robot for moving on snow.

Generally speaking, the systems described herein are directed to modularmobile robots, interchangeable features for use therein, a tooling armfor use therewith and an endless track for use therewith. The Figuresare not to scale and some features may be exaggerated or minimized toshow details of particular elements while related elements may have beeneliminated to prevent obscuring novel aspects. Therefore, specificstructural and functional details disclosed herein are not to beinterpreted as limiting but merely as a basis for the claims. Forpurposes of teaching and not limitation, the illustrated embodiments aredirected to a modular mobile robots, interchangeable features for usetherein, a tooling arm for use therewith and an endless track for usetherewith.

As used herein, the terms “having”, “comprises”, “comprising”,“includes” and “including” are to be construed as being inclusive andopen ended, and not exclusive. Specifically, when used in thisspecification including claims, the terms “comprises”, “comprising”,“includes” and “including” and variations thereof mean the specifiedfeatures, steps or components are included. These terms are not to beinterpreted to exclude the presence of other features, steps orcomponents.

As used herein, the terms “substantially”, “about” and “approximately”,when used in conjunction with ranges of dimensions, compositions ofmixtures or other physical properties or characteristics, is meant tocover slight variations that may exist in the upper and lower limits ofthe ranges of dimensions so as to not exclude embodiments where onaverage most of the dimensions are satisfied but where statisticallydimensions may exist outside this region.

As used herein, the coordinating conjunction “and/or” is meant to be aselection between a logical disjunction and a logical conjunction of theadjacent words, phrases, or clauses. Specifically, the phrase “X and/orY” is meant to be interpreted as “one or both of X and Y” wherein X andY are any word, phrase, or clause.

As used herein the term “operably connected to” means that the twoelements may be directly connected or indirectly connected that is theyare connected through other elements.

As used herein, the word “longitudinal”, when used in a context relatingto a direction of motion of a track, means the direction or axis that asingle track would travel along upon outfitting the track with one ormore wheels, sprockets, pulleys or other rotational drive mechanisms,placing the track on a surface, and actuating those driving mechanisms.As used herein, the word “lateral”, when used in a context relating to adirection of motion of a track, means a direction or axis parallel tothe axis of rotation of a wheel, sprocket pulley or other rotationaldrive mechanism when placed within the track and actuated to drive thetrack. As used herein, the words “longitudinal” and “lateral”, when usedin the context of a robot, refer to the direction or axis along which arobot would travel without turning, and a direction or axis along asurface of travel perpendicular to that axis, respectively. As usedherein, the term “chamfer” or variants refers to a sloping surface at anedge or corner, and does not imply any symmetry or particular anglewhich the sloped surface forms with any other surface.

What is claimed is:
 1. A mobile robot comprising a deployment mechanism;and a flexible tail attached to the deployment mechanism and extendingoutwardly from the mobile robot in a deployment direction; whereinactuation of the deployment mechanism moves the flexible tail andchanges the deployment direction of the flexible tail.
 2. The mobilerobot according to claim 1 wherein the deployment mechanism is arotational deployment mechanism, and wherein actuation of the rotationaldeployment mechanism rotates the flexible tail.
 3. The mobile robotaccording to claim 2 wherein the flexible tail rotates about an axisparallel to a lateral direction to the mobile robot.
 4. The mobile robotaccording to claim 2 wherein the flexible tail rotates about an axisparallel to an upward direction from the mobile robot.
 5. The mobilerobot according to claim 4 further comprising an endless track,comprising: a belt having an inner surface and an outer surface; and aplurality of chamfered cleats each having a contact surface, thechamfered cleats being attached to the outer surface defining anattachment area, and the contact surface shaped such that when the trackis laid on a flat solid surface, each chamfered cleat contacts the flatsolid surface with less area than the attachment area.
 6. The mobilerobot according to claim 5 further comprising a plurality of holes inthe belt, disposed between the chamfered cleats and shaped to allowteeth of a drive sprocket to pass through and to engage the belt fortransmitting force from the sprocket to the belt.
 7. The mobile robotaccording to claim 6 further comprising a dual v-guide comprising twoelongate, parallel protrusions which are spaced laterally from eachother, and are attached to the inner surface.